Needle loom



y 2, 1964 A. M. SMITH n 3,132,406

NEEDLE LOOM Filed March 16, 1962 8 Sheets-Sheet 1 INVENTOR. fizz/440:2flf 5311/2745 I Mi fimMW A. M. SMITH H May 12, 1964 NEEDLE LOOM FiledMarch 16, 1962 8 Sheet -Sheet 2 IIVVENTOR.

ora

May 12, 1964 A. M. SMITH 1| NEEDLE LOOM Filed March 16, 1962 8Sheets-Sheet 3 I I I I I I I I I M y 1964 A. M. SMITH :1 3,132,406

NEEDLE LOOM Filed March 16, 1962 8 Sheets-Sheet 4 0 INVENTOR.

BY jmd/fiag/Mm A. M. SMITH ll May 12, 1964 NEEDLE LOOM 8 Sheets-Sheet 5Filed March 16, 1962 a 2 M W W M M an y 1964. A. M. SMITH 11 3,132,406

NEEDLE LOOM Filed March 16, 1962 8 Sheets-Sheet 6 I Ma May 12, 1964' A.M. SMITH n NEEDLE LOOM 8 SheetsSheet '7 Filed March 16, 1962 m ATTORNEYSy 12, 1964 A. M. SMITH u 3,132,406

' NEEDLE LOOM Filed March 16. 1962 8 Sheets-Sheet 8 mmvroza. film mace52W; 47

United States Patent 3,132,406 NEEDLE LOOM Alexander M. Smith 1!, Elkin,N.C., assignor, by mesne assignments, to Fiberwoven Corporation, Eilrin,N.C., a corporation of North Carolina Filed Mar. 16, 1962, Ser. No.180,158 45 Claims. (c1. 28-4) The present invention relates to a needleloom and, more particularly, to an improved needle loom for needling aweb or batt of loosely matted fibers into a needled fabric. While theimproved needle loom of the present invention is particularly adapted toproduce a I needle fabric having a chain entanglement of fibersincluding subsurface interlooping and/or interlacing of fibers capableof use for blankets, wearing apparel, draperies or the like, it also maybe used to punch webs in the preparation of the web for use in makingpapermakers felt, upholstery fabrics, filters or the like.

The needle loom of the present invention is a specific improvement overthe apparatus disclosed in my copending United States patentapplications serially numbered 29,115, filed May 13," 1960, now UnitedStates Patent No. 3,090,099; and 31,910, filed May 26, 1960, now UnitedStates Patent No. 3,090,100, and is capable of producing needledproducts disclosed therein by the methods disclosed therein.

Needled fabrics, which are sometimes referred to as non-woven fabrics,derive their coherence and strength from interfiber entanglement andaccompanying frictional forces. Heretofore, needled fabric structureshave been produced in needle looms by subjecting a web or batt ofloosely matted fibers to a number of punchings on one side by an arrayof needles so as to reorient the fibers and compress the web, the webthen being subjected to a number of punchings on'the other side tofurther reorient fibers and compress the web. In some instances, theneedle looms have been provided with needles on opposite sides of theweb. In these instances, the needle boards have been displaced from eachother in the longitudinal direction of the web and have simultaneouslypunched the web from both sides. In my above-mentioned copendingapplications, a new and improved needled fabric structure havingincreased strength and uniform appearance on both sidesis produced by anovel needle loom wherein the web is alternately punched from one sideand then the other side by opposed needle boards each having an array ofneedles, the needles of one needle board traveling in mirror image pathsof the needles of the other needle board. By such an arrangement, thecontrol of the fiber orientation is ,positive throughout the web andchain entanglement of fibers is developed in contiguous rowsextending'lengthwise of the web, the fibers also interlocking betweenrows by interlooping and/or interlacing.

While the improvements in needle looms of the present invention areprimarily intended to produce a needled fabric such as disclosed in myaforementioned copending applications, certain improvements are alsocapable of being employed in any needle looms having oscillating needleboards.

An object of the present invention is to provide an improved needle loomhaving an oscillating needle board capable of high speed oscillations toand fro whereby a needled fabric may be produced at a high rate. Inlarge needle looms, the needle boards often have a length of 110 inchesand over and in some instances over 200 inches. The needle board whichhas its length extending across the width of the web is quite heavy anda large force is required to reverse its motion twice in each cycle.This force increases as the rate of oscillation increases and causes thedrive crank hearings to be heavily loaded.

3,132,406 Patented May 12 1964 CCv ing stresses due to its length and tothe high acceleration force which occurs when its motion is reversed.In'addition, the oscillation of a needle board at high speed transmitslarge periodic forces to the frame of a needle loom which must becarefully balanced if the machine is to have stability. Consequently,heretofore it was necessary to operate needle looms at relatively slowspeeds in order to eliminate excessive flexure of the needle board, toprovide practical crank bearing loads and to reduce the problemsresulting from imbalance.

Ancillary to the preceding object, it is a further object of thepresentinvention to provide a needle loom in which the masses, motionsand dimensions ef the moving parts are equal and arranged in a'mirrorimageof each other, such that the forces created by oscillation of theneedle boards and applied to the frame structure of the 100111 are equaland opposite and are thereby balanced, thus permitting fasteroscillation of the needle boards so that more production is accomplishedthan heretofore realized.

Another'object of the present invention is to provide an improved needleloom wherein a driving force is applied at uniform small intervalsacross the length of the needle board and thereby the fiexure of theneedle board due to forces caused by acceleration and deceleration isreduced.

Still another object of the present invention is to provide an improvedneedle loom in which moving parts and a spring means comprise a resonantsystem such that very small loads are placed on crank armsv and bearingsof said loom after oscillation has been started, such crank arms alsoserving to give a definite limit to the amplitude ofthe needle boardoscillation.

Still another object of thepresent invention is to providean improvedneedle loom comprising at least one needle board oscillating at highspeed to and fro between predetermined points, the needle loom includingmeans whereby a primary springdriving force can be uniformly appliedacross the needle board to counteract acceleration forces, the primarydriving'force being activated viding a needle loom which has anauxiliary power means to initiate a resonant spring system and anotherpower means for operation once the moving parts are oscillating.

A still further object of the present invention is to provide a needleloom having a needle board oscillating to and fro between predeterminedpoints, the needle loom being provided with means for storing uppotential energy at spaced small intervals across [the needle boardduring its movement in both directions and releasing this energy atspaced small intervals across the needle board at the ends of its stroketo reverse its direction.

An additional object of the presentinvention is to provide a needle loomstructure having needles mounted in a needle board which oscillate withan angular motion so that the axes of the needles move in pathssubstantially tangent to circles drawn about the center of rotation andpenetrate a fiber web and said structure having stiff and thereforeheavy members arranged near axis of rotation where acceleration forcesare relatively small and light members located away from the axis ofrotation where motion is greater and acceleration forces are relativelylarge.

One object of the present invention is to provide a needle loom havingneedles in a pair of opposed needle boards which oscillate in linearmotion, the needles of each board of the pair capable of alternatelypenetrating the web passes therebetween.

Another object of the present invention is to provide a needle loomhaving a minimum number of bearings per needle board which bearingsrequire maintenance and become a source of product contamination.

Another object of the present invention is to provide an improved needleloom having a plurality of opposed pairs of needle boards, the needlesof each board of a pair capable of alternately penetrating the web asthe web passes therebetween.

These and other objects and advantages of the present invention willappear more fully in the following detailed specification, claims anddrawings in which:

FIGURE 1 is a perspective view illustrating a needle loom of the presentinvention;

FIGURE 2 is a vertical end view partly in section and partlydiagrammatic of the needle loom of FIGURE 1, the view taken from theright side looking toward the left of FIGURE 1 and the top portion beingomitted and with the side cover plates also being omitted for purposesof clarity;

FIGURE 2a is a continuation of FIGURE 2 illustrating the top portion ofthe needle loom;

FIGURE 3 is a plan view partly broken away of the beam or rocker armstructure for one of the needle boards of the needle loom of FIGURE 1,the view being 180 out of phase with a view taken substantially on theline 3-3 of FIGURE 2;

FIGURE 4 is a vertical end view partly in section and partlydiagrammatic and illustrating a modified form of needle loom of thepresent invention;

FIGURE 5 is an enlarged fi'agmentary view illustrating the typicalspring means connection to the spar of the rocker arm structure ofFIGURE 4;

FIGURE 6 is a sectional view taken substantially on the line 7-7 ofFIGURE 5;

FIGURE 7 is an enlarged fragmentary sectional view of the connection forthe air spring means of FIGURE 5;

FIGURE 8 is a fragmentary plan view of the rocker arm structure of theloom of FIGURE 4, the view illustrating the positioning of the airspring means on the spars;

FIGURE 9 illustrates diagrammatically a modified spring meansarrangement for use with the needle looms of FIGURES 1 or 4 themodification including a leaf FIGURE 10 is an enlarged fragmentary viewtaken on the line 10-10 of FIGURE 9;

FIGURE 11 is a view diagrammatically illustrating another modifi cationof the spring means, the view showing the use of pairs of coil springsarranged axially of one another;

FIGURE 12 is a view illustrating diagrammatically another modificationof the spring means utilizing coil springs on each side of a pivotalaxis of the rocker arm structure;

FIGURE 13 is a view illustrating diagrammatically a further modificationof spring means and more particularly the use of air springs positionedon each side of the pivotal axis of the rocker arm structure;

FIGURE 14 is a view illustrating diagrammatically another modificationof the spring means and specifically the use of air springs mounted oneabove another and both positioned on the same side of the rocker armstructure;

FIGURE 15 is a view similar to FIGURE 14 but illustratingdiagrammatically a still further modification wherein air springs areused on opposite sides of a rocker arm structure;

FIGURE 16 illustrates a still further modification of spring meanscapable of use with the present invention;

' through FIGURE 17 is a fragmentary view diagrammatically illustratingapplication of the invention to a needle loom having at least one needleboard oscillating in a linear motion path between two points; and

FIGURE 18 is a schematic view of the air system for the air springs ofthe needle loom of FIGURE 1.

Referring now to the drawings wherein like character and referencenumerals represent like and similar parts and in particular to FIGURE 1,the needle loom of the present invention is illustrated in perspective.It will be understood that the needle loom of the present inventionreceives a web or batt of loosely matted fibers from any suitable sourceof supply, the web being fed to the needle loom by suitable conveyorstructure. Usually the loosely formed web comprises a plurality oflayers of fibers formed by a carding machine and fed therefrom to theconveyor which transfers the web to the needle loom. A web formed bydepositing fibers from an air stream may be used alone or in conjunctionwith a conventional lapper. Several means of web forming may becombined; thus, the fibers of the layers making up the web or batt maybe oriented variously with respect to the length of the web or batt asthe same passes through the needle loom.

The needle loom of the present invention has a frame structure generallydesignated at 10 which includes a framework of vertical and horizontalmembers made from channel sections, I-beams, box beams or the like andforming a box-like structure. In more detail, the frame structure 10 isprovided with two end sides 12 and 14 each made up of upper and lowerhorizontally extending channel shaped member 16 and 18 extending betweenand rigidly secured to a vertical channel 19 and to a verticalbox-shaped standard 20. Upper and lower cross beams 22 and 24,respectively, extend between the end sides 12 and 14 so as to form thesubstantially rigid box-like frame structure. Any suitable side coverplates 26, 28 and 30 may be utilized to enclose the end sides of theframe structure.

The box-like frame structure is suitably supported on a plurality ofpedestals 32. Preferably the pedestals 32 are individually adjustablewith respect to one another in order that the needle loom may besuitably leveled on the mill floor.

As best shown in FIGURES 1 and 2, the needle loom of the presentinvention is provided with a lower pair of opposed needle boardsgenerally designated at 34 and an upper pair of opposed needle boardsgenerally designated at 36. It will suffice to say at this time thepairs of needle boards 34 and 36, respectively, oscillate in an angularor curved path between predetermined points, it being understood thateach pair of needle boards 34 and 36 are moved simultaneously so thatthe needles of the boards of each pair alternately penetrate the web onboth sides. Also, it will suflice to say at this point in thespecification that the pairs of needle boards 34 and 36, respectively,move in opposite directions so that the needles of the lower needleboard of the pair 36 is penetrating the web at one place thereon whilethe needles of the upper needle board of the pair 34 is penetrating theweb at a different place thereon. A more detailed description of themovement of the pairs of needle boards 34 and 36 will appear later inthe specification.

The web of loosely matted fibers is diagrammatically shown in FIGURE 2by the broken line designated by the numeral 38. It enters the lowerportion of the needle m and passes between the lower pair of needleboards 34 and outwardly therefrom and upwardly around suitable guiderollers 40, 42 and 44 and then back horizontally through the centerunobstructed portion of the needle loom. Web. 38 is then guided upwardlyaround rollers 46, 48, and then horizontally between the upper pair ofneedle boards 36. As described in my aforementioned application SerialNo. 31,910, the feed of the web 38 the needle loom is in step-by-stepincrements with the needles of the needle boards penetrating the webwhile the web is in a dwell or stationary. It is also within the scopeof the present invention that the step-by-step movement of the web 38may be such as disclosed in my aforementioned application Serial No.29,115 wherein the web is moving as the needles of the needle boardbegin penetration and then is stationary as the penetration iscontinued. The rollers may be positively driven in stepby-stepincrements by a suitable oscillating rod 49 extend ing to a suitableone-way clutch and brake assembly 51.

The lower pair of opposed needle boards 34 includes an upwardly facingneedle board 50 having many of needles 52 extending therefrom and anupper downwardly facing needle board 54 having an array of needles 56extending downwardly therefrom. The needle boards 50 and 54 are carriedon one end of rocker arm structures 58 and 60, respectively. The rockerarm structures 58 and 60 are each pivotally mounted in the framestructure it on vertically spaced horizontally extending axes indicatedat 62 and 64, respectively, the axes 62 and 64 of the rocker armstructures 58 and 60 being intermediate the ends of the same. The upperpair of opposed needle boards 36 include a lower upwardly facing needleboard 66 having an array of needles 68 and an upper downwardly facingneedle board 70 having an array of needles 72. Rocker arm structures 74and 76 support the needle boards 66 and 70, respectively, for pivotalmovement about vertically spaced horizontal axes 78 and 80,respectively. From FIGURE 2, it will be apparent that all of the pivotalaxes 62, 64, 78 and 80 of the rocker arm structure lie in a commonvertical plane extending widthwise of the frame structure 10, themounting of the lower pair of needle boards being a mirror image of themounting of the upper pair of needle boards 36.

Preferably the array of needles 52 and the array of needles 56 of needleboards 50 and 54 travel in mirror image paths of one another as theyalternately penetrate the web 38. The path of penetration of the needles52 and 56 extends at an angle and opposite the direction of advancementof the web 38 between the needle boards 50 and 54. The preferable anglefor the needles 52 or 56 is a tangent of an are having a center ofcurvature common with the pivotal axes 62 or 64 of rocker arm structures58 and 60, respectively, the are having a radius equal to the distancebetween the desired point of penetration of the needle and therespective pivotal axes 62 or 64.

Each array of needles 68 and 72 of the upper needle boards 66 and 70also have mirror image paths of penetraion through the web 38. Theneedles 68 and 70 are arranged in the needle boards 66 and 7'3 so as toextend in a directionopposite to the direction of feed of the webbetween the needle boards. Their angles are determined in a similarmanner to the angles of the needles of the lower pair of needle boards.

Web guide plates 82 and 84 provide a path for the web 38 to travel asthe same passes between the pair of needle boards 34. The guide plates82 and 84 are provided with curved inlet portions defining an enlargedthroat and a plurality of holes (not shown) arranged so that an array ofneedles of the needle boards can pass therethrough.

Guide plates 82 and 84 may be secured to the frame structure in anysuitable manner. Guide plates 86 and 88 carried by the frame structure10 between the upperpair of needle boards 36 are substantially similarto the gmide plates 82 and 84 with the exception that the infeed throatportion is not quiteas large. It will be appreciated that the fabricstructure of the web has already been needled on both sides andcompressed considerably prior to entering between the guide plates 86and 88 so there is no necessity of providing a wide inlet throat.

The rocker arm structure 76 is best illustrated in plan view on FIGURE3. It will be appreciated that the other rocker arm structures 58, 60and 74 are substantially identical to the rocker arm structure 76 andtherefore the description of one rocker arm structure will suffice. Therocker arm structure includes an elongated axle memher 90 having its endportions 92 carried in suitable bearings 94 supported on the end sides'12 and 14. The axle member 9t? has rigidly secured thereto at spacedpoints along its longitudinal axis a plurality of spar members 96. Atubular member 98 (FIGURE 2) is rigidly secured to the ends of each ofthe spar members 96 whereas a beam member 100 extends through each ofthe spar members 96 and is secured thereto forward of and in spacedrelationship to the axle member 90. The needle board 70 which includesthe body member 102 is rigidly supported on the ends of the spar membersopposite the ends supporting thetubular member 98 by a clamp arrangement including the clamps 104 and 106.

The elongated needle board 70, as shown in FIGURE 3, as well as theother three needle boards, has a length which extends completely acrossthe width of the web 38 upon which it is operating. As mentioned at theoutset of the specification, such needle boards oftentimes have lengthsin excess of inches and, in some instances, as great as 200 inches ormore. Since the needle boards are supported on the end of the rocker armstructures, they have an angular path of motion as determined by theirdistance from their pivotal axes. Furthermore, as the needle boards areoscillated and, thus, decelerated and accelerated at the end of eachstroke, tremendous forces are created which must be resisted by theframe structure 10 through the axle member 90 and by the driving means.

In needle looms heretofore designed, the oscillation speed of the needleboards was limited because the reciprocating forces in such needle loomswere not effectively balanced. In other words,if the speed ofoscillation was increased to a certain point, the forces caused by thereciprocation of the needle board became so great as to cause dangerousvibrations in the frame structure and, consequently, the output of theneedle loom was limited to slow movement of the needle board or boards.By the arrangement of identical pairs of needle boards 34 and 36, asshown in FIGURE 2, oscillating in opposite directions in mirror imagemotion with one another, the

forces created by the oscillation of the needle boards are.

equal and opposite and thus cancel themselves out in the frame structureso that vibration is reduced to a minimum. The use of a weightedflywheel or crank counterweight as inneedle looms of conventional designcannot give the degree of balance achieved in the mirror image design ofthe present invention because the accelerations of the masses cannot bemade equal and opposite at all times. To obtain the balanced-needle loomof the present invention, the lower pair'of needle boards 34- and upperpair of needle boards 36 are guided in opposite directions ofoscillation by connecting rods .108-and 110, respectively, theconnecting rods 108 and 1410 being of equal length and operating off ofa crank shaft 112 having eccentrics 114 and 116 arranged 180out-of-phase with each other. The connecting rods 108 and 110 arerespectively connected to theeccentrics 114 and 116. A link 1018pivotally connected to the rocker arm structures 58 anddt) on the endsof their respective drive spars 145 (FIGURE 3 illustrates a similardrive spar 145 for rocker arm structure '76) at 120 and 122,respectively,;is also pivotally connected to theouter end o f theconnecting rod 108 at a midpoint 124. Likewise, the upper rocker armstructures 74 and 76 are pivotally connected together by a link .126which in turn is pivotally connected at 128 to the outer end ofconnecting rod 110. Upon rotation of the crank shaft 112, the connectingrods 108 and 110 move in opposite directions at all times and,consequently, cause the lower pair of needle boards 34 and upper pair ofneedle boards 36 to move in opposite directions whereby the forces ofthe respective pairs of needle boards and rocker arm structures areeffectively cancelled out. While FIGURE 2 shows the drive for thepairs34 and-36 of needle boards operatively connected to the drive sparsof the respective rocker arm structure on one side of the loom, it willbe appreciated that the drive is duplicated on the other side of theloom.

Crank shaft 112, which is mounted in suitable bearing blocks 129 carriedon opposite sides of the needle loom, is driven by a motor 130 throughsuitable fiuid coupling 136 and belting 132 and 140. However, anauxiliary starting motor 134 carried on the top of the frame structure10, as shown in FIGURE 1, is utilized to assist in starting theoscillation of the pairs of needle boards to overcome the initialcompression of the spring drive means to be described in detail later. Asuitable clutch arrangement is provided to disengage the auxiliary motor134 once the pairs of needle boards 34 and 36 and their respectiverocker arm structures are oscillating.

While the arrangement of the needle boards of the needle loom thus fardescribed wherein the pairs of needle boards are mounted in the framestructure in mirror image relationship to each other and have a drive inmirror image relationship to each other wherein forces created by theirmovement are equal and opposite at all times thus permitting increasedspeed of oscillation of the needle boards in an angular pattern, it willbe appreciated that the same mirror image principle of cancellingacceleration forces can be employed with needle boards moving in linearmotion. Also, it will be appreciated that such an arrangement furtherincreases production of the needled fabrics in that the utilization of aplurality of pairs of opposed needle boards increases the number ofpunches per square inch of area of needled fabric being discharged fromthe loom. In other Words, the needle loom of the present invention doesnot require a plurality of passes of the web through the machine toobtain sufficient fiber entanglement. In this respect, the productproduced by the needle loom of the subject invention has a softer handeven before napping, increased strength, and a uniform appearance onboth sides after napping as the fiber entanglement by the alternatelypenetrating needle boards of the pair is the same throughout thefinished web.

The needle boards of the present invention may be made according to thedisclosure in my copending application Serial No. 142,949, filed October4, 1961, and entitled Needle Board for Needle Loom and Method of MakingSame. While the aforementioned application discloses an improved needleboard and method of making the same, the needle board being lighter inweight than those needle boards heretofore used in needle looms, it willbe appreciated that such needle boards, because of the great number ofneedles carried thereby and because of their elongated length, stillhave a considerable mass.

An oscillating needle board decelerates and accelerates at the ends ofeach stroke; the maximum acceleration being directly proportional to thestroke length and to the second power of the speed of oscillation. Inthe desired range of operation this acceleration reaches a magnitudeequivalent to 35-60 times the acceleration of gravity. The needle boardbeing thus accelerated is subjected to a very great driving or resistingforce which in needle looms heretofore has usually been applied near theends of the needle board by crank arms. In the past, the magnitude ofthis acceleration with the resulting heavy load on the crank armbearings and the tendency of the needle board itself to bend or flexbetween the drive points resulted in uneven needle penetration.

Referring now to FIGURES 2, 3 and 18, it will be noted that the needleloom of the present invention is provided with spring means positionedbetween the frame structure and each of the oscillating rocker armstructures and needle boards, the spring means being capable of storingpotential energy as the needle boards move toward one end of theirstroke, the spring means releasing kinetic energy operatively uniformlyacross the needle board to assist the cranks in driving the needleboards in an opposite direction. By utilizing the spring meansarrangement of the present inventioncoupled with the crank means foroscillating the needle boards, it will now be evident that the load onthe crank bearings can be made very small and that a driving force isapplied at uniform small intervals across the entire length of the boardthereby eliminating fiexure in the needle board.

In more detail, the frame structure 10 is provided with a plurality ofcross beams 142 rigidly secured to and extending between the sides 12and 14 of frame structure 10, the cross-beams 142 being arranged withrespect to the rocker arm structures, as shown in FIG- URE 2. In theenvironment disclosed, there are two cross-beams 142 associated witheach rocker arm structure, the cross-beams extending parallel to thepivotal axis of the rocker arm structure and spaced on each side of suchpivotal axis. Each pair of cross-beams 142 is arranged on an oppositeside of a rocker arm structure from its needle board so as not tointerfere with the oscillation of the rocker arm structure or the feedof the web 38 through the needle loom. As shown in FIGURES 2 and 3, thetwo cross-beams 142 cooperating with the rocker arm structure 76 arearranged above and in spaced parallel relationship to the tubular member98 and beam 100 of the rocker arm structure.

A plurality of air springs 144 are positioned between the cross-beam 142and the tubular member 98. Each of the air springs 144 include a platemember 146 rigidly connected to the cross-beam 142, a second platemember 143 rigidly connected to the tubular member 98 and a flexiblewall 150 therebetween. Similar air springs 152 are positioned betweenthe cross-beam 142 and the beam 100 of the rocker arm structure 76. Whenthe rocker arm structure 76 is oscillated in a clockwise direction aboutits pivotal axis 80, as viewed in FIGURE 2, the beam 100 of the rockerarm structure moves toward the cross-beam 142 causing compression of theair in the air spring 152 and the build up of potential energy therein.Since there are a plurality of air springs 152 arranged across therocker arm structure 76, the build up of potential energy is uniformlydistributed across the rocker arm structure. The tubular member 98 movesaway from its cooperating cross-beam 142, and, consequently, there is adecrease in air pressure within the air springs 144 after they haveexpended their kinetic energy. At the end of the stroke, the connectingrod passes through dead center and then starts to return the rocker armstructure 76 in a counterclockwise direction. The potential energystored up in the springs 152 across the rocker arm structure 76 betweenthe same and the frame structure is then uniformly released as kineticenergy and thus a driving force is effectively applied to the needleboard across the length of the same through the rocker arm structure.Conversely, as the rocker arm structure 76 moves in a counterclockwisedirection, as viewed in FIGURE 2, potential energy is stored up in theair springs between the frame structure and the rocker arm structurethrough its tubular member 98, this potential energy being released askinetic energy at the end of the stroke in the counterclockwisedirection.

It will be noted that the cooperating rocker arm structure 74 isprovided with a plurality of air springs 154 and 156 which cooperatewith its tubular member 98 and beam 100, respectively. The air springs154 and 156 operate identically with the air springs 144 and 152 exceptthey are out-of-phase In other words, when the rocker arm structure 74is moving in a clockwise direction along with the rocker arm structure76, its air spring 154 between the cross-beam 142 and tubular member 98is compressed whereas its air spring 156 is expanded.

The lower pair of rocker arms 58 and 60 are similarly provided with airsprings 158, 160, 162 and 164. The action of the air springs 158, 160,162, 164 of the lower pair of rocker arm structures 58 and 60 isidentical with the action of the air springs 144, 152, 154 and 156 ofthe upper pair of rocker arm structures. Consequently, by having the airsprings arranged in this manner, there is also a balancing of the forcescreated by the conversion of potential energy into kinetic energy in therespective rocker arms at each end of their strokes.

Each of the air springs mentioned above is capable of having the meanair pressure therein varied and thus the eifective spring constant ofthe air springs can be varied. This is particularly important in that itis highly desirable that the air springs have a loW spring constant;that is, be as ineffective as possible when the needle loom is started.By eliminating or reducing the air pressure within the air springs priorto starting of the needle loom, the load on the starting motor ismaterially reduced. Once the needle loom has been started, then airunder pressure is applied to the air springs in order to provide themwith spring constant suitable for the desired speed of operation. Also,the invention contemplates providing individual adjustment of the airsprings while the needle loom is operating in order to obtain a desireddistribution of kinetic energy to the various needle boards.

Referring to FIGURE 18 which schematically illusstrates air springs 144,152, 154 and 156, it will be noted that those air springs ofv a pair ofrocker arm structures which compress on one stroke are in fluidcommunication with one another whereas the air springs functioningoppositely of the same pair of rocker arm structures are in fluidcommunication with one another. For example, the air springs 152 and 154are in fluid communication with one another by means of a flexible tubeor conduit 166 whereas the air springs 144 and 156 are in communicationwith one another by means of the conduit 168. Also, it will beunderstood each of the air springs 144 extending across the .rocker armstructure 76 are in fluid communication with each other, the samearrangement being provided for the other air springs 152, 154 and 156. Asuitable source of air pressure generally designated at 170 supplies airunder pressure through a valve 172 to a manifold 174. The manifold 174communicates with the conduit 166 by an auxiliary manifold 176 whereasauxiliary manifold 178 provides fluid communication between a manifold174 and the conduit 168. The auxiliary manifold 176 is provided with avalve 180 and a gauge 182 whereas the auxiliary conduit 178 is providedwith a valve 184 and gauge 186. Similarly the air springs for the lowerpair of rocker arms 58 and 60 are in communication with the manifold 174through similarly arranged conduits and auxiliary manifolds.

When the needle loom is started, the valve 172 is in the closed positionWhereas the valves 180 and 184 are open to atmosphere so that there isonly atmospheric pressure within the air springs. Once the needle loomis operating, then the valves 180 and 184 are closed to atmosphere butopen to the source of air pressure 170 to permit the flow of compressedair into the respective air springs. When the gauges have reached apredetermined value indicating a predetermined mean pressure in the airsprings, valves 180 and 184 are closed and thus the air springs areloaded to a specific desired spring constant. By operation of any of theindividual valves, the spring constant for any set of air springs can bevaried with respect to another set of air springs.

FIGURES 9 through 16 inclusive illustrate various modifications ofspring means capable of being utilized with the needle loom heretoforedescribed. The diagrammatic views illustrated in FIGURES 9 through 16disclose a single rocker arm structure, for example, the rocker armstructure 76, pivoted at P to the frame structure 10 and having theneedle board 70 mounted on one end thereof. FIGURE 13 illustrates thespecific example described with respect to FIGURES 1 through 3,inclusive, wherein air springs are placed on both sides of the pivot Pbetween the rocker arm structure and the frame structhe broken line B(FIGURE 10).

compression springs or tension springs or'both com-' Suitable bolts andstructure and extending pression and tension springs. 153 carried by'therocker arm through suitable apertures provided in the frame structuremay be utilized to retain the springs 144' and 152' in position.

FIGURE 14 illustrates a modified use of air springs wherein two separateair springs 144" and 152 separated by a portion 10' of the framestructure 10 are arranged one above the other and are capable offunctioning iden tically with the air springs 144 and 152. In themodification shown in FIGURE 14, the rocker arm structure is providedwith a yoke having a bearing plate 192 extending over the upper airspring 144". The yoke 190 is provided with'bolt members 193 at each ofits end whichslidably pass through apertures in'the portion 10' of framestructure 10 and is secured in a suitable manner to the rocker armstructure 76. When the rocker arm structure 76 of FIGURE 14 moves in acounterclockwise direction, the upper air spring 144" is compressed bythe bearing plate 192 of the yoke 190 whereas the lower air spring 152"is expanded. Clockwise move ment reverses the operation in that thelower air spring 152" is compressed while the upper air spring 144" isexpanded.

FIGURE 15 illustrates a modification similar to that of FIGURE 14 exceptthe yoke 190' is fixed to the frame structure 10 and has two bearingplates 195 and 197 fixed thereto.

FIGURE 11 illustrates a modification similar to FIG- URE 14 bututilizing a pair of coil springs 144" and 152'." separated by theportion 10 of frame structure 10. A bearing plate 192' carried on theupper end of a bolt 190 compresses the spring 144' upon counterclockwisemovement of the rocker arm structure 76 just as in the examples shown inFIGURE 14.

FIGURES 9 and 10 illustrate the use of a leaf spring 200 between theframe structure 10, the leaf spring being capable of functioning so asto store up potential energy and release kinetic energy upon movement ofthe rocker arm structure in either direction during its stroke. In moredetaiL'the rocker arm structure 76 is provided with a-pin 202 extendingupwardly through a suitable aperture :in leaf spring 200, the pin 202having a stop member 204 thereon. Upon movement'of the rockerarmstructure 76 in a clockwise direction, as viewed 'in FIGURE'9, thespring will engage a shoulder 206 on the pin 202 and be urged upwardlyas indicated by the broken line A (FIGURE 10). Upon counterclockwisemovement, the stop member 204 of the pin engages the opposite side ofthe spring and moves it to the position shown by It will be understoodthat such movement to either A or B stores up potential energy andconverts potential energy into kinetic energy upon changing direction ofthe stroke of the rocker arm structure so that the kinetic energy can beeffectively uniformly distributed across the needle board to provide theresults described in detail with respect to FIGURES 1 through 3,inclusive.

FIGURE 16 illustrates diagrammatically a spring means wherein a steeltorsion bar spring 181 is used in series with air springs 143. Therocker arm assembly 76 carrying needle board 70 is. rigidly fixed to thetorsion bar spring 181 and is pivoted at bearing P to the frame 10. Anarm member 183 having an axis transverse of the axis of the torsion barspring is fixed to an end of the torsion bar spring 181 and also at itsfree ends to two pairs of air springs 143 which are in turn mounted onthe frame 10. In this arrangement the loom can be started with low airpressure in the air springs, thus the motion 'mass, consistent withstructural rigidity,

form distribution of driving of the structure 183 will substantiallyfollow that of the rocker arm structure 76 and the torsion spring willbe ineffective. After the oscillation of the needle board has beenstarted, air pressure in the air springs can be increased to the pointwhere the structure 183 is substantially still and the torsion barspring is driving the rocker arm assembly 76.

For minimum stresses and forces it is desirable that the rocker armstructures 76 have a minimum weight or particularly in areas of maximummotion, that is near the needle board. This is a feature of the needleloom of the present invention. By the arrangement of FIGURE 16, theweight of air springs and their yoke structures is eliminated from therocker arm assemblies.

FIGURE 17 illustrates diagrammatically applying spring means to a needleloom of the type wherein the needle board is oscillated in a linearmotion path'by a conventional crank means. Heretofore, needle looms ofthis type were limited in their speed of operation in that the forcecreated on the needle board at the end of its stroke due to thedeceleration and acceleration when it was changing direction caused theneedle board to flex and crank bearing to be overloaded. By applicationof the spring means between the needle board and the frame structure ofthe needle loom, as heretofore described, uniforces is provided to theneedle board to thereby eliminate flexure of the needle board and assistthe crank driving means to properly oscillate the same. In more detail,the needle board 210 is reciprocated vertically in a linear motion bymeans of a pair of oppositely rotating crank arms 212 and 214. The crankarms 212 and 214 are connected to the needle board 210 by means ofconnecting rods 216 and 218, and guide rods 217 and 219, respectively. Aplurality of spring means 220 are provided across the needle board 210,the spring means 220 being capable of storing up potential energy andreleasing potential energy in both directions of the stroke. In theparticular example shown in FIG- URE 17, the spring means 220 is of thesame type 'as shown in FIGURE 14 and includes pairs of air springs 222and 224 separated by a portion 226 of the flame structure of the needleloom. A yoke structure 228 pr vided between the needle board 210 and theupper air spring 224 causes the upper air spring to compress when theneedle board 210 is moved in a vertically downward direction. The otherair springs 220 directly between the needle board 210 and the portion226 of the frame structure 227 compress when the needle board is movingvertically upwardly. Such an arrangement as just described results in auniform application of forces across the needle board at each end of itsstroke and thereby assists the crank to overcome the forces due toinertia of movement of the needle board.

It will be understood that the guide rods 217 and 219 could be extendedand connected to another needle board not shown but fitted with springsin a manner similar to that just described.

Referring now to FIGURES 4 through 8 inclusive, still furthermodification of the needle loom of the present invention is illustrated,this modification being capable of even higher production than theneedle looms just previously described. In FIGURE 4, which illustrates avertical end view partly in section of the modified needle loom, it willbe noted that there are four rocker arm structures 230, 232, 234 and 236pivotally mounted on the frame structure 238 for oscillating angularmotion about spaced pivotal axes 240, 242, 244 and 246, respectively.The pivotal axes of the rocker arm structures are vertically spaced fromeach other and lie in a common vertical plane extending transverse ofthe length of the web 248 passing through the needle loom. Each pivotalaxis is intermediate 'and midway between the ends of its respectiverocker arm structure.

Each rocker arm structure carries a needle board 250 at its oppositeends.

The needle boards 250 of the upper pair of rocker arm structures 230 and232 are arranged to oppose each other and likewise the needle boards 250of the lower pair of rocker arm structures 234 and 236 are arranged tooppose each other. In effect, there are four pairs of opposed needleboards 250 which the web 248 passes through and thus the web ispenetrated simultaneously at four different places, two of the placesbeing from one side of the web and the other two places being from theother side of the web. Guide plates 252 and 254 suitably supported onthe frame structure are provided between each pair of needle boards 259for guiding the web therebetween, the guide plates having the usualholes therein for passage of the needles therethrough.

As shown diagrammatically in broken lines, a pair of crank cams or arms256 and 258 are each provided with a pair of eccentrics, the crank camsor arms 256 and 258 being spaced equally from the vertical plane throughthe axes of the rocker arm structure and also equally from a horizontalplane positioned midway between the upper pair of rocker arm structuresand the lower pair of rocker arm structures. Connecting rods 260 and 262pivotally connected to the two eccentrics of crank cam or arm 256 are ofequal length and are both pivotally connected to the respective lowerrocker arm structures 232 and 236 of the upper and lower pairs of thesame. The connecting rods 260 and 262 are connected to eccentrics of thecrank cam or arm 256 which are outof-phase with each other and thus theconnecting rods always operate to move the rocker arms 232 and 236 inopposite directions about their pivotal axes 242 and 246.

A pair of connecting rods 264 and 266 are respectively connected to therocker arm structures 230 and 234 as well as to eccentrics of the crankcam or arm 258. The connecting rods 264 and 266 likewise are of equallength to each other and to the connecting rods 260 and 262 and moveopposite to each other and thus move the upper rocker arm structures 230and 234 of the pairs in opposite directions at all times. Crank cams orarms 256 and 258 are driven in the same direction by means of a beltdrive 270 or the like, it being understood that a suitable source ofpower is connected to one or the other or both of the crank arms.

As will now be evident, the needle loom shown in FIGURE 4 is acompletely balanced system both vertically and horizontally as allforces created by rotation of the crank arms 256 and 258 and movement ofthe needle boards 250 and their respective rocker arm structures areequal and opposite in vertical directions as well as horizontaldirections.

A slightly modified spring system is illustrated in FIG- URES 4 to 8 forstoring up potential energy and releasing kinetic energy uniformlyacross the needle boards on both sides of the needle loom. In moredetail, each rocker arm structure is provided with a pair of doubleacting air springs positioned on either side of its pivotal axis. Adescription with respect to one rocker arm structure and its needleboards will sufiice for all rocker arm structures.

Referring in detail to FIGURES 5 through 8, the rocker arm structure 230is provided with a center axle member 272 suitably journalled inbearings (not shown) supported in the side of the frame structure of theneedle loom. Spaced across and carried by the axle member 272 are aplurality of spars 274 which support at their outer ends the needleboards 250 in any suitable manner. Intermediate the respective outerends of the spars 274 and the axle member are crossbeams 276. Each ofthe cross-beams 276 are positioned immediately beneath a channel-shapedcross-beam 278 extending between the sides of a frame structure 238. Oneair spring 280 is supported on the upper side of the beam 278 whereasanother air spring 282 is supported immediately beneath the cross-beambetween the cross-beam 278 and the cross-beam 276 of the rocker armstructure. A yoke structure generally designated at 284 and having apair of rods 286 extending upwardly through suitable apertures 288in'the beam 278 is provided with a bearing plate at 290 for engaging thetop side of the uppermost air spring 280. e

As shown in FIGURE 7, the cross-beam member 278 is provided withfittings 292 having suitable passages 294 and 296 therein, the fittingsbeing adapted to threadedly receive the upper and lower air springs 280and 282, respectively. Air pressure may be adjustably supplied to theair springs through the passages 294- and 296 by suitable conduits orflexible tubing 298 and 300 in a manner similar to that previouslydescribed.

As will now be apparent, equal and oppositely directed kinetic energymay be applied uniformly to the respective needle boards on the outerends of the rocker arm structures as the rocker arm structures oscillatebetween their predetermined limits of oscillations as determined bytheir crank drive mechanism. It will be appreciated that the forces ofthe spring means coacting with one rocker arm structure of one pair isequal and opposite to the forces created by the spring means cooperating with the other rocker arm structure of a pair. Since the upperhalf of the needle loom is identical to the lower half, that is, itsmirror image of the same, andoperates in an opposite direction, there isalso balancing of forces between the pairs of rocker arm structures asthey oscillate.

It has been found highly desirable to have the needles of the opposedpairs extending at an angle to theweb pass ing therebetween. The needlesof an opposed pair of needle boards on one side of the vertical planethrough the axes of the rocker arm structures extend toward the needlesof the corresponding pair of opposed needle boards on the other side ofthe plane. The angle at which the needles extend relative to thehorizontal is determined in a manner similar to that heretoforedescribed with respect to the angle of the needles of the needle boardsof the needle loom shown in FIGURES 1 to 3, inclusive. In other words,the path of penetration of the needle through the web is a tangent to anarc having a radius equal to the distance between the pivotal axis andthe needle.

While the objects and the advantages of the needle loom of the presentinvention have been fully and effectively accomplished by the apparatusdisclosed herein, it will be understood that such needle looms aresubject to some changes and modifications without departing from theprinciples and scope of the invention involved. Therefore, theterminology used in the specification is for the purpose of descriptionand not limitation, the scope of the invention being defined by theclaims.

What is claimed is:

1. In a machine for needling a web of loosely matted fibers andproducing a needled fabric: a frame structure; means for advancing theweb through said frame structure; a needle board carrying an array ofneedles; means for moving said needle board to and'fro betweenpredetermined points so that said array of needles penetrate in and arewithdrawn from the web; a first spring means operatively positionedbetween said needle board and said frame for storing up energy when saidneedle board travels in one direction to apply a uniform driving forceacross said needle board when said needle board moving means is changingdirection of travel of the needle board to an opposite direction; and asecond spring means operatively positioned between said needle board andsaid frame structure for storing up energy when the needle board istraveling in the opposite direction'to apply a uniform driving forceacross said needle board when said needle board moving means is changingdirection of travel of the needle board to said one direction.

2. In' a machine for needling a web of loosely matted fibers andproducing a needled fabric: a frame structure;

means for advancing the web through said frame structure; a needle boardcarrying an array of needles; means for moving said needle board to andfro between predetermined points so that said array of needles penetratein and are withdrawn from the web; a first spring means operativelypositioned between said needle. board and said frame for storing upenergy when said needle board travels in one direction to apply auniform driving force across said needle board when said needle boardmoving means is changing direction of travel of the needle board to anopposite direction; a second spring means operatively positioned betweensaid needle board and said frame structure for storing up energy whenthe needle board is traveling in the opposite direction to apply auniform driving force across said needle board when said needle boardmoving means is changing direction of travel of the needle board to saidone direction; and means operative while said needle board is moving forchanging the effective spring constant of said first and second springmeans.

3. In a machine for needling a web of loosely matted fibers andproducing a needled fabric: a frame structure; means for advancing theweb through said frame structure; an elongated needle board extendingtransversely of the web and carrying an array of needles; meansoscillating said needle board to and fro between predetermined points sothat said array of needles penetrate in and are withdrawn from the web,said last-mentioned means including means connected to said needle boardat longitudinally spaced positions of the same for effecting to and fromovement; and spring means effective at each of said predeterminedpoints to apply a uniform driving force across said needle board toassist said needle board moving means in changing direction of travel'of said needle board at each of the said predetermined points.

4. The machine of claim 3 wherein said means connected to said needleboard includes arocker arm structure and wherein said spring meanscomprises a torsion bar spring rigidly connected to said rocker armstructure and operatively connected to said. frame structure so thatsaid needle board oscillates to and fro. in an angular motion path, anarm member rigidly connected to said torsion bar spring and having anaxis transverse of the axis of said torsion bar spring and air springmeans be'- tween said arm member and said frame structure, said airspring means being arranged to resist turning of said torsion bar springabout its axis in either direction. 5. The machine of claim 4 includingmeans to adjust air pressure of said air spring means while said needleboard is oscillating.

6. The machine of claim 4 wherein said arm member is connectedintermediate its ends to said torsionbar spring and wherein said airspring means includes a first pair of air springs, one air spring ofsaid first pair being positioned between said frame structure and oneside of one end of said arm member and the other air spring of saidfirst pair being positioned between said frame structure and theopposite side of same end of said arm member; and a second pair of airsprings, one air spring of said second pair being positioned betweensaid frame structure and one side of the opposite end of said arm memberand the other air spring of said second pair being positioned betweensaid frame structure and the opposite side of the opposite end of saidarm member.

7. The machine of claim 6 including means to adjust air pressure of theair springs of said first and second pairs 'while said needle board isoscillating.

8. The machine of claim '3 wherein said spring means includes aplurality of pairs of air springs, one of each of said pairs of airsprings storing energy between said needle board and said framestructure on movement of said needle board in one direction and theotherof each of said pairs of air springs storing energy between saidneedle board (and said frame structure upon movement of the needle boardin an opposite direction.

-by one of the air springs movement of the needle board in one direction15 9. The machine of claim 8 wherein said needle board includes rockerarms having a pivotal axis whereby the needle board oscillates to andfro in an angular motion path and wherein said one air spring of each ofsaid pairs is positioned forward of the pivotal axis between the framestructure and the rocker arm and said other air spring of each of saidpairs is positioned rearwardly of the pivotal axis between the rockerarm and the frame structure.

10. The machine of claim 8 wherein said needle board includes rockerarms having a pivotal axis whereby the needle board oscillates to andfro in an angular motion path and wherein said one air spring and saidother air spring of each pair are arranged one above the other, saidframe structure having a portion interposed between said one air springand the other air spring of each pair whereof each pair is storingenergy and said frame structure upon and the other air spring of eachpair is storing energy between said needle board and said framestructure upon movement of the needle board in an opposite direction.

11. The machine of claim 8 wherein said needle board includes rocker armstructure having a pivotal axis where by the needle board oscillates toand fro in an angular between the needle board motion path and whereinsaid one air spring and said other air spring of each of said pairs ofair springs are arranged on opposite sides of said rocker arm structure,and a yoke member fixed to said frame structure for each of said pairsof air springs, each yoke member having a first bearing plate engagingsaid one air spring of one pair of air springs on a side opposite theside engaging said rocker arm structure and -a second bearing plateengaging said other air spring of the same pair of air springs on a sideopposite its side engaging said rocker arm structure.

12. The machine of claim 3 wherein said spring means includes at leastone leaf spring positioned between said frame structure and said needleboard and capable of storing energy between said needle board and saidframe structure upon movement of said needle board in either direction.

13. The machine of claim 3 wherein said spring means includes aplurality of pairs of coil springs, one of said coil springs of each ofsaid pairs of coil springs being arranged between said needle board andsaid frame structure so as to store energy between said needle board andsaid frame structure upon movement of said needle board in one directionand the other coil spring of each of said pairs of coil springs storingenergy between said needle board and said frame structure upon movementof said needle board in an opposite direction.

14. The machine of claim 13 'wherein each pair of coil springs isarranged on a common axis, said frame structure having a portioninterposed between each pair of coil springs whereby one coil spring ofeach pair stores energy upon movement of said needle board in onedirection and the other coil spring of each pair stores energy uponmovement of said needle board in the opposite direction.

15. The machine of claim 13 wherein said needle board includes rockerarms having a pivotal axis whereby the needle board oscillates to andfro in an angular motion path and wherein said one coil spring of eachof said pairs is positioned forward of rocker arms of said framestructure and the other coil spring of each of said pairs is positionedbetween the rocker arms and the frame structure rearwardly of saidpivotal axis.

16. In a machine for needling a web of loosely matted fibers andproducing a needled fabric: a frame structure; means for advancing theweb through said frame structure; a rocker arm structure pivotallymounted intermediate its ends to said frame structure on a pivotal axisextending substantially transverse of the web; at least one elongatedneedle board carried by said rocker arm structhe pivotal axis and theture adjacent one of its ends, said elongated needle board verse of theWeb; an array of needles carried by said needle board; means connectedto said rocker arm structure for oscillating the same betweenpredetermined points and thereby causing the array of needles topenetrate and be withdrawn from the web; and means for uniformly storingup potential energy between said needle board and said frame structureduring movement of said needle board in both directions and respectivelyreleasing uniform kinetic energy across the needle board in an op positedirection at each end of the stroke of travel of the needle board.

17. The machine of claim 16 wherein said last-mentioned means includesat least one air spring positioned between said frame structure and saidrocker arm forward of said pivotal axis and at least one air springpositioned between said frame structure and the same side of said rockerarm structure rearwardly of said pivotal axis, and means connected toeach air spring for adjusting air pressure of the air spring while saidrocker arm structure is oscillating.

18. The machine of claim 16 wherein said last-mentioned means includesat least a pair of air springs arranged one above the other, said framestructure having a portion thereof extending between the air springs ofthe pair, one of the air springs of the pair being positioned betweenthe rocker arm structure and the frame structure and adapted to becompressed upon movement of the rocker arm structure in one directionand the other air spring of the pair being operatively connected to therocker arm structure wherein the same is compressed upon movement of therocker arm structure in an opposite direction and means connected toeach air spring of said pair for adjusting air pressure in the samewhile said rocker arm structure is oscillating.

19. In a machine for needling a web of loosely matted fibers andproducing a needled fabric: a frame structure; means for advancing theweb through said frame structure; a rocker arm structure pivotallymounted intermediate its end to said frame structure on a pivotal axisextending substantially transverse of said web; an elongated needleboard carried by said rocker arm structure adjacent one of its ends; asecond elongated needle board carried by said rocker arm structureadjacent the other of its ends, both said elongated needle boards havinglongitudinal axes extending substantially parallel to each other andtransverse of the web, each of said needle boards having an array ofneedles; means connected to said rocker arm structure for oscillatingthe same between predetermined points and thereby causing alternatepenetration of the web by the respective needle boards; and means foruniformly storing up potential energy between each of said needle boardsand said frame structure during movement of said needle boards in bothdirections and respectively releasing uniform kinetic energy across eachof the needle boards in an opposite direction at each end of the strokeof travel of each of the needle boards.

20. The machine of claim 19 including means for adjusting saidlast-mentioned means while said rocker arm structure is oscillatingabout its pivotal axis.

21. In a machine for needling a web of loosely matted fibers andproducing a needled fabric: a frame structure; a first pair of spacedrocker arm structures pivotally mounted intermediate their ends on saidframe structure and having spaced parallel pivotal axes; a second pairof rocker arm structures pivotally mounted intermediate their ends onsaid frame structure and having spaced parallel pivotal axes, thepivotal axes of said first and second pairs of rocker arm structureslying in a common plane, a pair of opposed elongated needle boardscarried respectively on the corresponding ends of said first pair ofrocker arm structures; a second pair of opposed elongated needle boardscarried respectively on the corresponding ends of said second pair ofrocker arm structures; each of said needle boards of each pair of needleboards having an array of needles; means for advancing the web throughsaid frame structure between said first pair of opposed needle boardsand then between said second pair of needle boards; and means foroscillating said first pair of rocker arm structures between predetermined points and said second pair of rocker arm stiuctures betweenpredetermined points whereby needles of said first and second pairs ofopposed needle boards each respectively effect penetration of the webalternately from opposite sides of the same.

22. The machine of claim 21 wherein said last-mentioned. means includescrank means; at least one con necting rod connected to said crank meansand operatively connected to said first pair of rocker arm structures; asecond connectingrod connected to said crank means and operativelyconnected to said second pair of rocker arm structures, said first andsecond connecting rods being connected to said crank means 180out-of-phase with each other whereby forces created by oscillation ofsaid pairs of needle boards are equal and opposite and thereby balanced.

23. The machine of claim 21 wherein said last-mentioned means includes afirst link pivotally connected to each rocker arm structure of saidfirst pair; a second link pivotally connected to each rocker armstructure of said second pair; crank means, a first connecting rodconnected to said crank means and to said first link; a secondconnecting rod connected to said crank means and said second link, saidfirst and second connecting rods being connected to said crank means 180out-of-phase with each other whereby forces created by oscillation ofsaid pairs of needle boards are equal and opposite and thereby balanced.

24. The machine of claim 21 including means for uniformly storing uppotential energy between each rocker arm structure of each of said pairsof rocker arm structures during oscillation of said rocker armstructures in both directions and respectively releasing uniform kineticenergy across each of the rocker arm structures in an opposite directionat the end of the stroke of travel of the same.

25. The machine of claim 24 wherein said means includes a plurality ofair springs coacting between said frame structure and the rocker armstructures of. said first and second pairs, half of said air springsbeing compressed upon oscillation of the rocker arm structures in onedirection and the other half being compressed upon oscillation of therocker arm'structures in an opposite direction.

26. The machine'of claim 25 including means to adjust air pressure insaid air springs while said pairs of rocker arm structures'areoscillating, said last-mentioned means including a source of airpressure, fluid connecting means between said source of air pressure andsaid air springs and valve means in said fluid connecting means.

27. The-.machine'of 'claim'21 wherein said last-mentioned means includesa first crank means spaced from one side of the common plane in whichthe pivotal axes of the first and second pairs of rocker arm structureslie; a second crank means spaced from the opposite side of the plane; afirst connecting rod connected to said first crank means and to onerocker arm structure of said first pair, a second connecting rodconnected to said first crank means and to a corresponding rocker armstructure of said second pair of rocker arm structures; a thirdconnecting rod connected to said second crank means and to the otherrocker arm structure of said first pair of rocker arm structures; and afourth connecting rod connected to said second crank means and to theother rocker arm structure of said second pair of rocker arm structures,said first and second connecting rods and said third and fourthconnecting rods being of equal length and connected to said first andsecond crank means respectively 18 out-of-phase whereby forces createdby oscillation of said pairs of needle boards are equal and opposite andthereby balanced.

28. The machine of claim 21 wherein said first pair of opposed needleboards is arranged vertically above said second pair of opposed needleboards.

29. A needle loom for needling a web of loosely matted fiberscomprising: a frame structure; a first pair of opposed elongated needleboards each having an array of needles; a second pair of opposedelongated needle boards positioned above said first pair and each havingan array of needles; means supporting each of said pairs of needleboards respectively in said frame structure for oscillating angularmotion about vertically spaced axes; means operatively connected to saidsupporting means of each pair of needle boards'for simultaneouslyoscillating. said pairs of needle boards in opposite directions wherebyforces exerted on said frame structure by both pairs of needle boards isequal and opposite and means for feeding the web successively betweenfirst and second pairs of needle boards whereby the web is alternatelypenetrated from each side by the array of needles of each needle boardof each pair of needle boards.

30. The needle loom of claim 29 including a plurality of air springscarried by said frame structure, at least one air spring cooperatingwith each needle board on oscillation of the same in one direction tocompress and store up potential energy and then release kinetic energyat the end of the stroke of the needle board and at least one of saidair springs cooperating with said needle board when said needle board isoscillating in an opposite direction to compress and store up potentialenergy and release kinetic energy when the needle board reaches the endof itsstroke in the opposite direction.

31. The needle loom of claim 30 including means to adjust air pressurein said air spring when said pairs of needle boards arev oscillating.

32. A needle loom for needling a web of loosely matted fiberscomprising: a frame structure; a first rocker arm structure and a secondrocker arm structure, said first rocker arm structure being pivotallymounted in said frame structure intermediate and midway between its endsand said second rocker arm structure being pivotal. ly mounted in saidframe structure intermediate and midway between its ends, the first andsecond rocker arm structures having vertically spaced parallelhorizontal pivotal axis; a needle board carried on each end of each ofsaid first and second rocker arm structures and each needle board havingan array of needles, the needle boards on corresponding ends of saidfirst and second rocker arm structures opposing each other; a thirdrocker arm structure and a fourth rocker arm structure, said thirdrocker arm structure being pivotally mounted in said frame structureintermediate and between its ends and said fourth rocker armstructurebeing pivotally mounted in said frame-structure intermediate and betweenits ends, said third and fourth rocker arm structures having verticallyspaced parallel horizontal pivotal axes lying in a common plane with andspaced vertically from the pivotal axes of said first and second rockerarm structures; a needle board carried on each end of each of said thirdand fourth rocker arm structures, and each having an array of needles,the needle boards on the corresponding ends of said third and fourthrocker arm structures opposing each other; means for oscillating saidfirst and second rocker arm structures simultaneously in the samedirection while oscillating said third and fourth rocker arm structuressimultaneously about their pivotal axes 180 out-of-phase with theoscillation of said first and second rocker arm structures; and meansfor advancing the web horizontally between the needle boards of saidfirst and second rocker arm structure and then horizontally between theopposed needle boards of said third and fourth rocker arm structures.

33. The needle loom of claim 32 wherein each of said rocker armstructures includes an axle member and a plurality of horizontallyspaced spar members carried on said axle member, the needle boards beingsupported at the ends of the spar members.

34. The needle loom of claim 33 including a plurality of air springmeans, at least two air spring means being supported between each sparmember and said frame structure on opposite sides of said axle member,each air spring means being capable of storing up potential energy uponoscillation of the rocker arm structure in both directions and releasingpotential energy upon oscillation in the respective opposite directions.

35. The needle loom of claim 34 including means to effectively adjustthe spring constant of said air spring means while the needle loom isoperating.

36. The needle loom of claim 32 wherein the array of needles of theopposed needle boards on corresponding ends of the first and second, andthird and fourth rocker arm structure respectively arranged to penetratethe web in a path at an angle to and opposite to a path of penetrationof opposed needle boards at the opposite corresponding ends of saidfirst and second, and third and fourth rocker arm structures,respectively.

37. The needle loom of claim 32 wherein said oscillating means includescrank means, a plurality of connecting rods, one of said connecting rodsbeing connected between crank means and each of said first, second,third and fourth rocker arm structures.

38. The needle loom of claim 37 wherein each of said connecting rods isof equal length.

39. In a machine for needling a web of loosely matted fibers andproducing a needled fabric: a frame structure; a pair of elongatedneedle boards each carrying an array of needles, the array of needles ofone of said needle boards opposing the array of needles of the other ofsaid needle boards; means for advancing a web through said framestructure between the array of needles of said needle boards; means forsimultaneously moving said needle boards to and fro betweenpredetermined points so that there is alternate penetration of the webfrom opposite sides by the respective arrays of needles of said pair ofneedle boards; a first spring means operatively positioned between eachof said pair of needle boards and said frame structure for storing upenergy when said pair of needle boards travel in one direction and forreleasing the stored up energy and applying the same as a uniformdriving force across each of said pair of needle boards when said needleboards are changing direction of travel to an opposite direction; and asecond spring means operatively positioned between each of said pair ofneedle boards and said frame structure for storing up energy when saidpair of needle boards travel in the opposite direction and for releasingthe stored up energy and applying the same as a uniform driving forceacross each of said pair of needle boards when said pair of needleboards are changing direction of travel to said one direction.

40. The machine of claim 39 wherein said means simultaneously movingsaid needle boards includes means to move said pairs of needle boards ina linear path.

41. The machine of claim 39 wherein said means for simultaneously movingsaid pair of needle boards includes means to move each of said pair ofneedle boards in an angular motion path, the angular motion path of oneof said pair of needle boards being a mirror image path of the other ofsaid pair of needle boards.

42. The machine of claim 39 wherein said first and second spring meanseach includes air springs and means to apply air pressure to said airsprings after the machine is operating.

43. A needle loom for needling a web of loosely matted fiberscomprising: a frame structure; a first pair of opposed elongated needleboards; a second pair of opposed elongated needle boards positionedvertically above said first pair; a third pair of opposed elongatedneedle boards horizontally spaced from said first pair; a fourth pair ofopposed elongated needle boards positioned vertically above said firstpair of needle boards, each needle board of said pairs of needle boardshaving an array of needles; means for simultaneously oscillating all ofsaid pairs of needle boards in said frame structure betweenpredetermined points with said first and third pairs moving in mirrorimage paths of said second, and fourth pairs respectively and with saidfirst and second pairs moving in opposite direction from the directionsof movement of said third and fourth pairs respecticely; and means forfeeding a web successively between the pairs of needle boards wherebythe web is alternately penetrated from each side by the respective arrayof needles of each needle board of each pair of needle boards.

44. The needle loom of claim 43 wherein each pair of needle boards hasan equal mass and an equal inertia with respect to each of the otherpairs of needle boards whereby the needle loom is balanced verticallyand horizontally.

45. The needle loom of claim 43 including drive means for saidoscillating means, said drive means including a drive shaft, a mainmotor operatively connected to said drive shaft, an auxiliary startermotor, and a fluid coupling connecting said auxiliary motor to saiddrive shaft whereby said auxiliary motor may be disconnected after saidmain motor and said auxiliary start the loom.

References Cited in the file of this patent UNITED STATES PATENTS202,252 Field Apr. 9, 1878 1,720,574 Schieferstein July 9, 19292,004,709 Phillips June 11, 1935 2,004,725 Johnson June 11, 19352,217,967 Phillips Oct. 15, 1940 2,601,432 Clements June 24, 19522,845,687 Howard Aug. 5, 1958 2,896,302 Costello July 28, 1959 2,936,064Schuessler May 10, 1960 2,993,585 Musschoot July 25, 1961 3,047,306Easton July 31, 1962 UNITED STATES PATENT OFFI CE CERTIFICATE OFCORRECTION Patent No. 3 132,406 May 12, 1964 Alexander M, Smith 11 It ishereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

In the grant lines 2 and 12 and in the heading to the printedspecification, line 4 name of assignee for "Fiberwoven Corporation" eachoccurrence, read The Fiberwoven Corporation Signed and sealed this 27thday of October 1964.,

(SEAL) Attest:

' ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

1. IN A MACHINE FOR NEEDLING A WEB OF LOOSELY MATTED FIBERS AND PRODUCING A NEEDLED FABRIC: A FRAME STRUCTURE; MEANS FOR ADVANCING THE WEB THROUGH SAID FRAME STRUCTURE; A NEEDLE BOARD CARRYING AN ARRAY OF NEEDLES; MEANS FOR MOVING SAID NEEDLE BOARD TO AND FRO BETWEEN PREDETERMINED POINTS SO THAT SAID ARRAY OF NEEDLES PENETRATE IN AND ARE WITHDRAWN FROM THE WEB; A FIRST SPRING MEANS OPERATIVELY POSITIONED BETWEEN SAID NEEDLE BOARD AND SAID FRAME FOR STORING UP ENERGY WHEN SAID NEEDLE BOARD TRAVELS IN ONE DIRECTION TO APPLY A UNIFORM DRIVING FORCE ACROSS SAID NEEDLE BOARD WHEN SAID NEEDLE BOARD MOVING MEANS IS CHANGING DIRECTION OF TRAVEL OF THE NEEDLE BOARD TO AN OPPOSITE DIRECTION; AND A SECOND SPRING MEANS 